Internal-combustion engine



Feb. 17. 19,25.

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I N VEN TOR.

Patented Feb. 17, 1925.

' UNITED STATES CLEO F. BRADNEY, OF DENVER, COLORADO.

INTERNAL-COMBUSTION ENGINE.

Application led April 21, 1923. Serial No. 633,740.

-To all whom, it may concern:

` tions upon a reciprocating element secures an equable and constantly acti-ve movement of a shaft with which said element is connected.

Another object ofthe invention is toV provide an engine of the above described type in which two reciprocating elements working in interconnected units co-operate to effeet the rotation of the shaft by evenly baln anced impulses.

A further object of the invention resides in providing an explosion engine which .owing to the small number of parts required in its operation, ma be 'produced at low cost and mantaine in perfect operative condition at a minimum expense, and still other objects reside in providing an engme of the above described type the parts of which are readily accessible for repair and a-djustment, in providing a simple and etlicient arrangement for lubricating and cooling the working parts of the engine, in providing an arrangement of ports and controlling devices which insure a substantially -complete scavenging during each stroke of the reciprocating element, in direct-ing the fuel along a course which causes 1t to be preheated by the heat of the engme, and 1n other details of construction and novel ar- .by a hollow rod to operate conjointly in axially alined cylinders. Two separate combustion chambers formed between the cyhn.- ders and preferably exteriorly thereof are alternately charged and exhausted by the movement of .a reciprocating valve element which in order to properly time the passage of fuel to and from said chambers is prefcably composed of two co-operating memrs The cylinder is open at one end to pro-v vide for'the direct connection of theiconnected plstons with a rotary crank shaft and the valves are operated by direct con- .nection with the same shaft without the ini terlnedlary of cams or other adjustment requiring parts `found in many engines of similar' character.

'Another advantageous feature of the invention is that the fuel in its course to the compression spaces of the cylinders passes through the hollow piston stem and it is a` part of my invention to assemble two units each comprising axially alined cylinders and a pistonelement as hereinabove described in interconnection to co-operatively effect the rotation of one crank shaft by successive power impulses at regular intervals in its rotary motion.

In assembling two units in this manner, one valve element is sufiicient to regulate the admission of fuel to all the cylinders thereof and by proper relative placement of the pistons in said units and a corresponding larrangement of the ports controlled by the movement of the valve element, the motive impulses of the engine may be timed so as to act upon the reciprocating elements of theI two units synchronously in opposite directions, with the effect that the crank shaft with) which said elements are connected is subjected to twoforces acting simultaneously at opposite sides of its axis of rotation in the direction of its rotary motion.

Having thus brieily described tht` most distinctive features of my invention I will now proceed to explain the same in detail with reference to the drawings in the several views of which corresponding parts are similarly designated and in which- Figure 1 represents a longitudinal section through an engine constructed in accordance with my invention in which two units are co-operatively assembled as hereinabove described;

Figure 2, alongitudinal section along the line 2 2, Figure 1;

Figure 3, a transverse section showing the combustion or tiring chambers of the engine, taken on the line 3 3, Figure l, and drawn to an enlarged scale;

Figure 4, a similarly enlarged section in the plane indicated by the line 4 4, in

l.Figure 1;

Figure 753i ajfiagmentary vertical section in either 'ofthe planes designated. by the lines -5 in Figures 3 and 4;

Figure 6, an enlarged cross section along the line 6-6, Figure 1;

Figure 7, a similar section taken on the line 7-7, Figure 1;

Figures 8, 9 and 10, diagrammatic views showing in vertical section, the relative positions of the piston elements of the two units and of the valve members controlling the supply of motive fluid thereto; and

Figure 11, a section on the line 11-11, Figure 9.

Referring more specifically to the drawings, the reference characters A and B d esignate the two units of-the duplex engine illustrated in Figure 1, each unit comprising two cylinders 5 and 6 connected in axial alinement by an interposed coupllng or union 7. o

The union 7 and the thereto ad]oim ng ends of the cylinders are provided with flanges for their connection by coupling bolts 8.

Each unit is closed at its upper end, and for convenience in manufacture the two units may to this end be provided with a single head 9 fastened in the usual manner by means of bolts 10. A second head 12 disposed in the lower cylinder of each unit is fastened at the lower end of a tubular core 13 axially coincident with the cylinders and rigidly connected to the upper head by means of a bolt 14. 1

f The head thus suspended is channeled and ported and the hollow core is likewise ported for the passage of motive fluid toand from the compression spaces of the engine as will hereinafter be more fully described.

Two pistons 15 and 16 fitted for reciprocation in the cylinders ofeeachunit are connected by a hollow rod 17 which is slidably fitted around the core 13. y l.

The coupling 7 between the cylinders vof cach unit has a restricted throat 18 through which the rod 17 passes in fluid tight engagement with a bushing 19 of anti-friction material. The coupling or unit provides the firing or combustion chambers in which, during the operation of the engine, the combustible charges intermittently supplied thereto, are ignited.

In order to simplify the construction of the engine but one coupling is used when two unitsl are assembled for co-operation and it will be apparent that the construction of the coupling as shown in the drawings and hereinafter described, in so far as the arrangement of 'its chambers and passages is concerned, the same is in a single unit engine.

-'The uwe aringehembere deeigneied inthe *drawings by the reference characters 2O and 21, are formed oppositely and separate'from each other as best shown in Figures 2 andl 3 and the are in the operation of the engine alternate y connected with a source of fuel element whic works in a chamber 22 extending lengthwise between the two units.

In the construction illustrated in the drawings the corresponding cylinders of the units are like their unions, formed en bloc and the three major componentl pai-ts of the engine, namely: the connected upper cylinders, the common union and the connected lower cylinders are provided with central bores which are axially alined and 'which conjointly form the cylindrical valve cham-l ber which extends the entire length of the engine and which has a' number of ports the arrangement of which will later be described in detail.

It is to be understood wit-hout further illustration that in a single unit engine, the valve chamber is in like manner formed exteriorly of the alined cylinders.

The upper piston of the connected pair of each unit has-an axial open-en-ded bore and is rigidly fastened upon the upper portion of the open ended tubular connecting rod extending in said bore. Thelower piston is closed at its upper end and fastened at the lower end of the rod, and it has a skirt which fits slidably in the cylinder and around the stationary head at the end of the hollow core.

Screwed in the lower end portion of the skirt and held in place by Ia flange 23 of angle section bolted at the extremity of the sa1ne, is a bearing 24 for the support of the pin 25 of a connecting rod 26 which extends downwardly through the open end' of the lower cylinder for its connection with the crank shaft 27. L

The latter is mounted in bearings-at opposite sides of a case 28 which asis usual in engines of this type, is partially filled with a lubricating oil and provides a support for the cylinders which are -fastened upon a Aflange at the upper edge of the case by bolts 29.

The valve-element of the enginehereinbefore referred to, comprises two tubular members 30 and 31 one of which is slidably fitted in the other and which are conjoint-ly fitted for reciprocation in the cylindrical valve chamber. The two valves are operated by direct connection with the crank shaft and the latterhas to this end, two cranks 32 and 33 disposed between the cranks 34 and 35 of the pistons and con-.

nected with the valve-members by means of connecting rods 36 and 37.

The cylinders are provided with surrounding water jackets 38 connected by a corresponding passage 39 in the coupling, and the firingchambers in the latter are equipped with the usual spark plugs 40 for -supply throu h the. intermediary of a valvethe ignition of their charges through the medium of' a timingl element in an electric circuit in which the plugs are connected.

' f'lhe inner valve member 30 is closed at its ends and'both valve members are provided with ports which-in the operation of the engine, register with each other and with ports connecting the valve chamber with the cylinders and the firing chambers, as will hereinafter be more fully described.

' T he two cranks connected with the piston elements of the two units, are placed opposite each other at 18() degrees, and the two cranks of' the valve-members are arranged with relationto each other and the direction of rotation to compel the inner valve member to move slightly' in advance of the other l member, and they are disposed relative to the piston cranks to co-operate with the pistons in timing the admission ot' motive fluid to and from the firing and compression chambers. Having thus described the general construction ot' the component elements of myv improved engine, I will now proceed to explain the arrangementof 1ts ports and passages relatlve to lts cylmders, pistons and .firing and valve chambers, and the successive steps yin the operation at which said ports and connections are brought in communication with each other' for the passage of motive fluid to and from the chambers. y

The stationary head 12 in the lowercylin der of each unit has a duct or passage 41 for the connection of the hollow core 13 which in the operation serves as a conduit for the transference of motive' fluid through the hollow piston rod to and from the compression spaces of the engine, with an intake port/'42 in the wall of' the cylinder, through the intermediary of a port 43 in the skirt of the lower piston.

The port 42 connects with a carburetor which as usual supplies the combustible mix- Y ture of` air and carbon gases, and in a duplex engine of the type shown in the drawings, the two int-ake ports are connected with one pipe 44 leading from the carburetor, by means of a manifold 45.

The compression spaces of the engine hereinbefore repeatedly referred to, are in the upper cylinder the space 46 between the upper piston and the upper cylinder head, and in the lower cylinder the space 47 between Vthe closed end of the lower piston and the suspended head 12.

The last mentioned head has in addition vto the passage 4l, a duct 48 connecting the connected respectively with the upper and lower cylinders by openings 53 and 54 as shown in Figures 4 and 5, and in the duplex engine, the two firing chambers common to both units, each connect with an upper c vliuder of one unit and a lower cylinder of the other unit so that when a charge is ignited in either chamber the piston elements of the two units are moved synchronously in opposite directions, and the crank shaft is in cousequence subjected to two equal impulses simultaneously acting in the direction of rotation at opposite sides of its axis.

The admission of motive fluid to the firing chambers is controlled by the valve element and each chamber has a portl opening in the valve chamber as shown at 55 and 56 in Figvures 2, 3 and 11, and the two valve members have two pairs of ports 57 and 58 which at a certain point in their reciprocating moveof the ,respective firing chamber, as illustrated in Figure 3.

The upper cylinder of each unit has an intake port 59 which connectswith the carburetor and as in the lower ,cylinder hereinbefore described, the` openings of the two upper cylinders in the duplex engine are counected' to. one conduit 60 leading from the carburetor, bymeans of a manifold (il.

A duct'62 in the upper piston of' each unit has a port 63 adapted to register with the intake port 59, and a second port 64 which simultaneously registers with a port 65 in the stationary hollow core. 13 inside the tubular piston rod 17. Another passage 66 in the piston connects its interior with a port 67 between the cylinder and the valve chamber at the same time that the port 64 of the passage 62 connects with the intake port. 59 as hereinbetore described, and the valve members 2,1 and :lo have two ports 68 and 69 adapted to simultaneously register with the port 6T.

In the duplex engine two ports in each valve member are brought in register with opposite ports of the valve ehan'xbers counecting respectively with the upper cylinders of the two units at different periods in the operation ofv the engine as will hereinaft'lel be more fully explained.

e Stationary core of each unit has furthermore opposite ports 70 adapted to connect its interior with the lower compression space 47 and the'port 65 at the upper end of the core is intended to connect its interior wlth the upper compression space 46 through the medilun of a passage 76 in the .upper c vlinder and a port 77 which registers with the port 65 when the respective piston element` approaches the end of its downward stroke.

Each cylinder is provided with upper and lower exhaust ports-71 and 7 2 which are alternately covered and uncovered by the respect1ve pistons in the operation of the engine, and corresponding exhaust ports of the two units of the duplex engine are prefer-` ably connected by ymanifolds 73 and 74 shown in Figures 2 and. 7.

Havin thus described the 'mechanical construction of my improved engine, I will now proceed to eXp-lain its operation by reference-to Figures l8 and 11 of the drawlngs.

units are shown as moving in the direction ofthe arrows 75 and 76, that of the unit at the right hand side of the engine being near the end of its upward stroke and that of the other unit being in a corresponding position near the end of its downward stroke. v With the pistons thus positioned, the charge compressed in the upper co-mpression spacey46 of the right hand unit by the upward movement of the piston element `passes from the space through the duct 66 of the piston 15, the port 67 in the cylinder wall and the ports 68 and 69 of thevalve members, into the valve chamber and the charge simultaneously compressed in the lower compression space 47 of the left handy other unit and during the continued movement of the crank shaft to its upper dead center, said portgare entirelyv opened and the charge of compressed fuel is completely dischar ed from the valve chamber into the firing c amber abovereferred to.

With the elements ofthe engine in the above described position as illustrated in Figures 1, 2 and 8, the duct 62 of the upper piston of the unit' at the ri ht hand side of the engine'connects the inta eport 59 of the respective cylinder withy the hollow core 13 and the fresh charge of fuel entering the latter passes througi the ports 70 into the lower compression space 47. The duct 41 of the lower piston in theleft hand unit of the engine is at the same time in' register with the inta-ke port 42 and the charge passes into the hollow core to enter the upper compression space 46 of the unit through the registering ports 56 and 77 and the passage 76 of the upper piston.

During the continued movement of the shaft, the connection between the compression spaces 46 and 47 of the two units and the valve chamber is rapidly closed by the upward motion of the outerlyalve member -31 while the piston cranks their dead center position, and immediately thereafter I n Figure 8, the piston elements ofthe two' the communication between the valve chamber and the firing chamber 20 is closed and the compressed charge thus confined in the latter, is ignited through the medium of the respective spark plug.

The force of expansion of the ignited .fuel produces an impulse which causes the piston elements of the two units to move synchronously in oppositeY directions until they approach the end of their stroke when the abm'e described conditions' are reversed as illustrated in Figure 10.

In this position of the" elements of the engine, the lower intake port of the right hand unit connects with the upper compres,- sion space as hereinbefore described with reference to the left hand unit and the upper intake port of the latter connects with the lower compressionl space. At the same time the'fuel compressed in the compression space 47 of the right hand unit by movement of the lower piston toward the stationary head 12, is permitted to enter the firing chamber 21 which connects with the upper cylinder of the right hand unit and with the lower cylinder of the left hand unit and after the cranks of the iston elements have again passed their dea center positions, the charge confined in said chamber is i ited and im pels the pistons in the opposite directions.

The exhaust ports which normally are covered by the pistons, are opened for the discharge of spent fuel when the pistons approach the end of their strokes and they remain open until after the pistons have commenced their return movement, and it will b'e evident that by this arrangement, the compression spaces are completely scavenged during each movement of the piston elements.

- The two valve members operating conoperate not only to rapidly cover and uny cover the ports of the cylinders but to open said ports during their movement in one direction and continuously cover them during their return movement by a simple crank motion of comparatively vsmall radius or throw.

` The method of'feeding the charge of fuel to the compression spaceslof the cylinders throu h a central core is advantageous in that 51e fuel is preheated before compression and subsequent ignition and that by absorbing the heat, it cools the parts with 1 which it comes` in contact, and it will be seen that owin to the same feature of con-A struction, liqui inthe charge can not reach', the crank case since it is completely vaporized by the heat of the engine before com?.l pression and that in consequence, the 1ubricant in the crank case is never thinned by leakage of raw fuel as frequently occurs in engines in which the 'compression spaces are in direct connection with the carburetor.

diately after t e valve membersA It will further be understood that inasmuch as the impulse produced by the ignition of the fuel in the combustion spaces acts directly upon the iston element for the compression of theresh charges without the intermediary of the crank shaft 'or its bearings, an equable movement is obtained free from liability to knocks and waste motions, and wear of the connection between the iston element and the shaft and of the sliaft and its bearings is materially reduced.

It will also be apparent that in the manner illustrated, an engine composed of more than two units may be assembled by means of integrally formed corresponding parts Ainterconnected by bolts as., shown and described.

` Figure 9 of the drawings but indirectly referred to, in the preceding description, shows the parts in the osition they occupy immeave reached the position shown in Figure v10, when by the continued movement of the pistons past their dead centers, the valve members are displaced to close the connection`between the compression spaces of the units with the valve chamber, and the latter is fully connected with the respective irmg chamber by complete registration of the ports 58, 57 and 55.

Having'thus described my invention, what I claim and desire to secure by Letters Patent is: t

1. Inan internal combustion engine, axially alined piston chambers, ported plstons in` said chambers, each chamber being provided with a port for the intake of fuel and having a compression space and a combustion space at opposite sides of the respective piston, and a rod connecting the pistonsA and havin a passage co-operating with the ports of t e chambers and the plstons to conduct fuel entering through the intake port of-either piston chamber to the compression space of theother chamber at determinate periods in the movement of the pistons.

2. In an internal combustlon engine, axially alined iston -chambers provided with ports for t e intake of fuel and having combustion spaces at their inner. ends, ported pistons in said chambers, stationary Aheads co-operat' g with the pistons for the compression of el in s aces at the outer ends ofthe chambers, an a rod'connectmg the pistons and having a passa e co-operating with the ports of the cham rs and the pistons to conduct fuel entering through the port of either piston chamber to the compression space of the other chamber at determinate?. 'periods in the movement of the pistons.

, 3. In an internal combustion engine, axially alined piston chambers provided withy ports for the intake of fuel and having combustion 'spaces at .their inner ends, ported pistons in said chambers, a tubular rod conpiston stem, the variousports being ary rangedrelative to each other and the interior of the rod to conduct fuel entering through the port of either piston chamber through the rod and the core, to the compression space of the other chamber at determinate periods-in the movement of the pistons.

'4. An internal combustion engine. comprising axially alined piston chambers having vcombustion spaces at their inner ends, ported pistons in said chambers, a tubular rod connecting the pistons, a stationary head co-operating With one of the pistons for the compression of fuel in a space at the outer end 'fof the respective piston chamber, a stationar channeled head co-o erating with the ot er piston to compress uel in a space at the outer end of the other piston chamber, the piston chambers being provided with ports for the passage of fuel from their com ression spaces to the respective combustlon spaces, a hollow ported core on the channeled head, within the piston rod, and a valve element lcontrolling the 'passage of fuel from the compression space of each piston chamber toy the combustion space of the same, the various ports and channels being arranged relative to each other and the interior of the piston rod to -conduct fuel entering through the intake port of either piston chamber, through the rod and the core to the compression space ofthe other chamber at determinate periods in the movement of the pistons.'

ally alined piston chambers provided with ports for the intake of fuel, ported pistons 1n said chambers, a tubular rod connecting the pistons, a stationary head co-operating with one of the pistons for the compression of fuel in a s ace of the respective piston chamber, a channeled head co-o erating with the other iston to compress uell in a Space of the ot er iston chamber, and a orted hollow core ead in ri .'d connection with the other head 5. In an internal'combustion engine, axi-f ed on the channeled and exten 'ng in the piston rod, the various pression space of the other piston chamber at determinate pcrlods 1n the movement of p the pistons.

Iof fuel in a space of the respective chamber', a channeled head within the trunk of the other piston, co-operating with said piston for the compression of fuel in the space between them, a crank shaft having a connection with the trunk piston through the open end of the respective chamber, a tubular rod connecting the pistons, and a ported hollow core on the channeled head. within the piston rod, the various channels and ports being arranged relative to each other and the interior of the` rod to conduct fuel entering through the intake port of either piston chamber, through the rod and the core to the compression space ,of the other chamber at determinate periods in the lnovelnent of the pistons.

7. In an internal combustion engine, a unit comprising two sections having axially' alined piston chambers, a section interposed between the others,` having two tiring chambers connected respectively with the piston chambers at the inner ends thereof, interconnected pistons in the piston chambers, stationary heads co-operating With the pistons for the compression of fuel in spaces at the outer ends of the chambers, and a valve element adapted to provide a path for fuel from the compression spaces yof the piston chambers to the firing chambers at determinate periods in the movement ofthe pistons.

.8. Aninternal combustion engine comprising two units each having axially alined piston chambers, interconnected -pistons in the chambers of each unit, each chamber being provided with ports for the ingress and egress of fuel and each chamber having a compression s ace and a combustion space at opposite si es of its respective piston, two firing chambers each connected with the combustion spaces vof piston chambers at oppbsite ends of the two, units, and a valve element adapted to connect the compression spaces of piston chambers at opposite ends of the two, units simultaneously with the tiring chamber connected with the respective combustion spaces at determinate perlods in the movement of the pistons.

9; An internal combustion engine comprisling' two units each ha-vingaxially alinedpiston chambers, interconnected pistons in the chambers of each unit. each chamber bcing provided with ports for the ingress and egress of fuel and each. chamber having a compression space and a combustion space at opposite sides of the respective piston, two firing chambers each connected with the combustion spaces of piston chambers at opposing ends of the two units, a valve element adapted to connect the compression spaces of piston chambers at opposite ends of the two units simultaneously with the firing chamber connected with the respective combustion spaces at determinate periodsin the movement of the pistons, and means for comlurting fuelentering through the ingress ports of piston chambers at opposite ends of the units simultaneouslyto the compression spaces of the chambers at the other ends of the same. .s

IO. An internal combustion engine comprising two units each having axially alined piston chambers provided with ports for the ingress and egress of fuel, intercom neted pistons in the chambers of each unit, each chamber having a compression space and a combustion space at opposite sides of its piston, a valve chamber ported to providea path for fuel from the compression spaces to the combustion spaces of the piston chambers of the two units, and a valve element moving in unison with the pistons and controlling the ports of the valve chamber to connect the compression spaces of piston chambers at opposite ends of the two units simultaneously with the respective combustion spaces at determinate periods in the movement of the pistons.

l1. An internal combustion engine comprising two units each having axially alined piston chambers, provided withport-s for the ingress and egress of fuel, interconnected pistons in the chambers of each unit, each chamber having a compression space and a combustion space at opposite sides of its piston` a valve chamber ported to provide a path for fuel from the compression spaces to the combustion spaces of the pion cham-v bers yof the two units, al crank shaft connected for rotation by the movement of the pistons` and a valve element having a crankconnection with the shaft andy adapted to control the ports of the, valve chamber so as to connect the compression spaces of piston chambers at opposite ends of the two units simultaneously with the respective combustion spaces at determinate periods in the movement of the pistons.

12. An internalv combustion engine comprising two units each having axially alined piston 'chambers provided with ports for the ingress and egress of fuel, interconnected pistons in the chambers of each unit, each chamber having a compression space and a combustion space at opposite sides of its piston. two firing chambers eachI connected with the combustion spaces ofpiston chambers at opposite, ends' of the 'two units, a valve chamber having ports connecting with the tiring chambers and with the compression spaces, and a valve elelnentmoving in unison with the pistons and adapted to control the ports of the valve chamber so as to connect the compression spaces of piston chambers at oppositeends of the two units simultaneously with one of the firing chambers.

13. An internal combustion engine comprising axially alined piston chambers ported for the ingress and egress of fuel, a compression head at an end of one chamber, a ported hollow compression head at the opposite end of the other chamber, and hollow interconnected pistons having ports co-operating with those of the piston chambers and the hollow compression head for the circulation of fuel in the operation of the engine.

14. An internal combustion engine comprising axially alined piston chambers ported for the ingress and egress of fuel, a compression head atan end of one chamber, a ported hollow compression head at the opposite end of the other chamber, a ported connectionbetween the hollow compression head and the piston chamber closed by the other head, hollow pistons having ports co-operating with those of the piston chambers and the hollow compression head for the circulation of fuel in the. operation of the engine, and a member connecting the pistons and controlling the passage of fuel through the ports ofl the connection between the heads.

15. An internal combustion engine comprising axially alined pistony chambers ported for the ingress and egress of fuel, a compression head at an end of one chamber, a ported hollow compression head at the opposite end of the other chamber, a

ported tube connecting the hollow compression head with the piston chamber closed by the other head, hollow pistons having ports co-operating with those of the piston chambers and the nollow compression head for thev circulation of fuel in the operation the engine, and a tubular connection between the pistons, fitted around the ported connecting tube of the hollow compression head.

16. An internal combustion engine comprising axially alined piston chambers ported for the ingress and egress of fuel, a compnession head at an end of one chamber, a ported hollow compression head at the opposite end of the other chamber, rigidly connected pistons connected in tandem for conjoint movement in the piston chambers and adapted to control the circulation of fuel through the ports of the chambers and of the hollow compression head, and means for conducting fuel from the compression spaces of thecylinders to the combustion spaces of the same.

17. An internal combustion engine comprising axiallyl alined piston chambers .ported for the ingress and egress of fuel,

a shaft, hollow and ported pistons rigidly connected in tandem for conjoint movement in the chambers in driving connection with the shaft, a compression head at an end of one of the chambers, a ported compression head at the opposite head of the other chamber inside of the respective piston and means for conducting fuel from the compression spaces of the cylinders to the combustion spaces ofl the same.

In testimony whereof I have aftixed my signature.

CLEO F. BRADNEY. 

